Organic Gems · uncommon
Pearl
Pearls are organic gems formed inside mollusks. Natural pearls are extremely rare; most pearls today are cultured by inserting a nucleus into the mollusk.
Also known as: june birthstone, organic gem, cultured pearl.
Pearl properties at a glance
| Type | Organic Gems |
|---|---|
| Chemical formula | CaCO3 |
| Mohs hardness | 3 |
| Crystal system | orthorhombic |
| Luster | pearly |
| Streak | White |
| Cleavage | None |
| Fracture | Uneven |
| Specific gravity | 2.7 |
| Transparency | opaque |
| Common colors | White, Cream, Pink, Black, Gold |
| Rarity | uncommon |
Geology & background
Forms inside mollusks when nacre (aragonite and conchiolin) is deposited in layers around an irritant.
Pearls have been treasured for at least 6,000 years and were once more valuable than diamonds.
How to identify Pearl
- Check whether the specimen's color and texture match typical Pearl examples.
- Photograph a fresh surface in natural light and avoid shadows, glare, or wet surfaces.
- Use hardness, streak, luster, grain size, and locality together; no single trait is enough for every specimen.
Full Pearl identification guide: checklist, home tests and look-alikes →
Pearl vs similar stones
Not sure it isn't something else? Side-by-side comparisons with the stones most often confused with Pearl.
Where Pearl is found
Pearl is reported from multiple localities or geological settings. Exact locality should be verified from specimen provenance, maps, or field notes.
How much is Pearl worth?
| Entry-level specimen | $50 |
|---|---|
| Typical collector specimen | $500 |
| Premium specimen | $100000+ |
Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.
Common uses
- Jewelry
- Decorative objects
Interesting facts
- The only gem created by a living organism
- Natural pearls are now almost exclusively sold at auction
- Cleopatra allegedly dissolved a pearl in vinegar and drank it
Care & safety
Treat Pearl as a collector specimen unless hardness, cleavage, and fracture are confirmed.
Avoid inhaling dust. Do not cut, grind, or polish unknown specimens without eye protection and a properly rated respirator.
Pearl FAQ
What is Pearl?
Pearls are organic gems formed inside mollusks. Natural pearls are extremely rare; most pearls today are cultured by inserting a nucleus into the mollusk.
How much is Pearl worth?
Entry-level Pearl specimens sell for around $50, a typical collector specimen for about $500, and premium pieces for $100000 or more. Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.
How hard is Pearl?
Pearl has a Mohs hardness of 3. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
Where is Pearl found?
Notable sources of Pearl include Japan, Australia, French Polynesia, China, and Persian Gulf. Forms inside mollusks when nacre (aragonite and conchiolin) is deposited in layers around an irritant..
What is Pearl used for?
Pearl is used for jewelry and decorative objects.
